Masteriyo exposes a high-impact PHP object injection flaw
Masteriyo - LMS through 3.4.0 permits PHP object injection. The vector requires no user interaction and rates confidentiality, integrity, and availability impact as high, but the endpoint, parameter, deserialization operation, gadget chain, and exact post-injection effect are not disclosed.
- Component
- Masteriyo - LMS
- Plugin slug
learning-management-system- Affected
- n/a through 3.4.0
- Safe version
3.4.1- Published
- Sep 11, 2026
This CVE was published Sep 11, 2026 and is one of 19 known issues for this plugin.
Update, patch or deactivate.
Update Masteriyo - LMS to 3.4.1 or later. The authoritative affected data explicitly marks 3.4.1 unaffected. The application-level fix must prevent untrusted serialized data from reaching PHP deserialization and should use a constrained non-object data format for client-controlled values.
A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.
Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.
Technical description
Unauthenticated PHP Object Injection in Masteriyo - LMS <= 3.4.0 versions.
CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H